There is a reason that she doesn't want to go to bed, if she was molested she probably (knowingly or unknowingly) thinks of that around bedtime, assuming it happened in the evening/night. Maybe you could try having her sleep somewhere else, like the two of you could sleep in the living room, you can make going to bed something fun by reading, a game, whatever. I don't know. Either way, don't be afraid to admit you need help! This is a challenging situation.